Solar Power Solutions for Mobile Computing.

Xantrec 300 / Sunlinq portable solar solution

Here’s a solution based on the Sunlinq 25w panel and a Xantrec 300 Plus combo lead-acid battery/inverter. Its very similar to my own solution apart from the fact that this one weighs nearly 10KG!!!

A number of blogs seemed to have picked up on this solution today and are quoting 11-12 hours charging time. This figure is a little misleading. The battery capacity is about 240w/hr and based on a reasonable 5-hour per day full-sun rate its going to take 10 hours. That’s a minimum of 36 hours duration! In middle-Europe, you’ll be waiting for 3 full days of sun!

The other point to consider is that you need to take all your AC converters with you (weight problem) and should recon on 20% energy loss by converting from 12v -> 110V and down to 12, 16, 19 or whatever voltage your device takes. Hardly efficient. Alternatively you can buy 12v car adaptors for all your equipment (can get expensive.)

My recommendation is to use a combination of a Li-ion battery with variable DC output (I’m using the TabletKiosk/Tekkeon MP3400) and a lead-acid battery (I’m using a 2.5kg 6Ah part) This gives you the best of both worlds (lead-acid flexibility and Li-Ion light weight) and cuts the total weight right down to under 4KG. At also avoids having to operate a dangerous 110v. Capacity with my solution is around 130W/hr but here’s the key. Don’t use a notebook PC, use a UMPC. They are far more efficient. With a normal UMPC you’re good for 10 hours of computing on a fully charged system (around 7 hours full-sun charge time.)